Need clarification on RTH parameters

[Fjleiter]

Ended up with my first crash, only damage was to gimbal and camera.

Drone was about 20 foot away from me and about 30 foot up in the air, approx. 30 foot from its home point.

Was filming my son and battery was low but more than enough for minute or two of footage I wanted to get. It got low enough it went to RTH mode. Here is what I don't understand...

I have RTH height set to 100 feet because it is primarily woods around me. However, I was under the possibly mistaken impression that under a certain distance from home point it would just fly to home point and land regardless of height. (Was thinking I heard like 50 or 100 feet away)
This time I was talking to my son and didnt hear it announe it was RTH... I did'nt notice the message on the display in time to cancel it. (Totally my fault)

Anyways...it ascended or tried to ascend to 100 feet straight into the forest canopy where it acted like a weed whacker for a few minutes before dropping like a rock...straight down. Amazingly, only damage was to gimbal and camera even though it landed upside down.

Is there a minimum distance from home point for RTH height?

 

[msinger]

It your Phantom is within 20 meters of the home point, it'll land at its current location when RTH is initiated.

 

[eaglegoaltender]

It your Phantom is within 20 meters of the home point, it'll land at its current location when RTH is initiated.

Good to know - I had it happen to me when I was close to that 20m range and a low battery triggered return to home. I was in a wide open space so I thought I would just let it do it's thing and come home. However it fooled the heck out of me and landed (safely) pretty well where the rth was initiated. I was at about the same height as distance at the time also. Now I know why it did what it did - thanks msinger.

Edit: quick question here - I have only carried out a Phantom calibration a couple of times and it was in my back yard. A lot of my flights are in an area about 4km away (couple of miles) - when I get the "ready to fly signal" - VM states "home point has been updated" - does that mean my "home point" is where I am flying no matter the distance from the area of calibration - or does it reference where I calibrated a couple of miles away? That instance where I just let the RTH go through it's process but it landed pretty well where it was at the time (as noted above) - I let the RTH happen since I wanted to see if it headed toward my place a couple of miles away where it was calibrated just to see if in fact that was my home point - however as said (and now I know why) it just landed where it was.

 

[msinger]

when I get the "ready to fly signal" - VM states "home point has been updated" - does that mean my "home point" is where I am flying no matter the distance from the area of calibration - or does it reference where I calibrated a couple of miles away?

It means the home point was marked at the Phantom's current location. The home point is never set during a compass calibration.

 

[eaglegoaltender]

It means the home point was marked at the Phantom's current location. The home point is never set during a compass calibration.

Thank you msinger - you're just a wealth of knowledge on the subject of Phantoms and helping others. Much appreciated.

 

[Fjleiter]

It your Phantom is within 20 meters of the home point, it'll land at its current location when RTH is initiated.

I was within 20 meters, wonder why it went straight up instead of landing where it was.

 

[msinger]

Did you check out your TXT flight log to see if it reveals what happened? You can upload it here. If you'd like us to review it, please post a link back here.

 

[MultiMegalomaniac]

I was within 20 meters, wonder why it went straight up instead of landing where it was.

Depending on your RTH Parameters, your drone may ascend straight up to your RTH altitude before landing. This may still happen even within 20 meters of the Home Point.

 

[msinger]

This may still happen even within 20 meters of the Home Point.

Why would the drone ascend to the RTH altitude when its within 20 meters of the home point?

 

[Vzr1]

Why would the drone ascend to the RTH altitude when its within 20 meters of the home point?

Low battery?

 

[msinger]

At the critically low battery level, the Phantom will auto land at its current location. It'll completely bypass RTH.

 

[WilliamM]

On a side note, are you sure 100" is well over the tallest tree anywhere nearby? I also primarily fly near wooded area and have mine set at 50 meters.

Sent from my HTC 10 using PhantomPilots mobile app

 

[Pharm]

Why would the drone ascend to the RTH altitude when its within 20 meters of the home point?

Because HE didn't initiate it. The low (not "critical") battery initiated it. When that happens, the distance to the home point is irrelevant. It will ascend to the RTH altitude, then fly above the home point before descending even if the home point is 2 feet away. If HE had initiated that close to home, it would have autolanded right where it was.

I had a similar incident. Fortunately, I had backed up a few feet and was out from under the tree canopy right before it happened because my battery was getting low. I had just recently re-read the manual and so I knew what was happening and simply cancelled the RTH and landed manually. A few seconds difference and I'd have been in the same boat.

 

[Vzr1]

I was showing my missus how it returns to home and it failed....doh! Took the drone as high as it could go in GPS mode then went about 10 metres forward then hit RTH and it said returning but sort of went straight down not even near me.

 

[eaglegoaltender]

Took the drone as high as it could go in GPS mode then went about 10 metres forward then hit RTH and it said returning but sort of went straight down not even near me.

Bet she was impressed - LOL!

Well that further supports what msinger stated: "If your Phantom is within 20 meters of the home point, it'll land at its current location when RTH is initiated".

 

[Vzr1]

Bet she was impressed - LOL!

Well that further supports what msinger stated: "If your Phantom is within 20 meters of the home point, it'll land at its current location when RTH is initiated".

Lol. Well that sucks if your at a lookout like I was today 20 metres and it would be over the cliff face landed.

It looks low but it is up high the house roof you can see is about 80 metres down

 

[eaglegoaltender]

Well that sucks if your at a lookout like I was today 20 metres and it would be over the cliff face landed.

Yikes, never thought of that - or if you happen to be over water within that range of 20m or so from your home point. I suppose lesson here is avoid RTH unless it is an absolute emergency! Good point!

Odd looking area there at that "look out" - is that a stone/brick retaining wall surrounding it or a kind of road-way, hard to tell? From the air it looks like an area with an alter for some ancient sacrifices - LOL. Nice photo nonetheless.

 

[WilliamM]

Lol. Well that sucks if your at a lookout like I was today 20 metres and it would be over the cliff face landed.

It looks low but it is up high the house roof you can see is about 80 metres down

It's been stated in other forums that if your not in an area that is open and flat (that's ideal for a HP), you at least need to step back over 25 meters from any drop-off and away from any tall object before setting a HP. Because of this feature.

Sent from my HTC 10 using PhantomPilots mobile app

 

[WilliamM]

Yikes, never thought of that - or if you happen to be over water within that range of 20m or so from your home point. I suppose lesson here is avoid RTH unless it is an absolute emergency! Good point!

Odd looking area there at that "look out" - is that a stone/brick retaining wall surrounding it or a kind of road-way, hard to tell? From the air it looks like an area with an alter for some ancient sacrifices - LOL. Nice photo nonetheless.

There's a very good reason for this feature. First under most conditions 20 meters is close enough to be considered being home. Next, if it didn't do this and the drone was only say 10 or 15 meters out, would you want or need it to go to the RTH altitude first go a few meters over, just to land.

Sent from my HTC 10 using PhantomPilots mobile app

 

[eaglegoaltender]

Next, if it didn't do this and the drone was only say 10 or 15 meters out, would you want or need it to go to the RTH altitude first go a few meters over, just to land.

Correct and the only reason I could ever see for employing RTH that close to home would be to do what the OP did - and that was to quickly show someone how RTH works.

Thanks for the other info relating to HP - "you at least need to step back over 25 meters from any drop-off and away from any tall object before setting a HP. Because of this feature."

Always learning.